According to the current prior art, synchronizer rings, which are employed in synchronizing devices of sliding clutch transmissions, for example, made of nonferrous metal are used or rings made of base metals are used, which are coated with or glued to various materials, for example, carbon fiber plates or sintered or sprayed materials such as molybdenum coatings as is disclosed in DE 10 2006 057 486 A1, DE 10 2004 060 016 A1, and DE 100 35 489 A1.
The existing systems have the disadvantage that, e.g., molybdenum coatings tend to be eaten away in the event of high contact pressure threes and sliding speeds, since, although the oil is displaced well from the friction contact, due to the lack of porosity and the lack of springback of the layer resulting therefrom (sponge effect), no new oil can flow in to prevent the eating away.
Carbon materials are, on the one hand, very costly and, on the other hand, the application to greatly varying synchronizer ring geometries is difficult, since a resulting adhesive joint can act as a flaw, at which the covering easily detaches and which can consequently result in comfort problems. In addition, complex application tools are necessary.
A friction material which is also for use in synchronizing devices is disclosed by DE 10 2006 061 414 A1, wherein complete synchronizer rings are no longer used as the friction material, but rather friction lining elements, referred to in the scope of this publication as friction elements or friction lining pads or pads or friction pads, are arranged in a synchronizer ring with recesses wherein the friction lining pads are arranged in the recesses. The synchronizer ring functions as a carrier or cage in this case. All applications are to be operated using such friction pad systems (FPS) in this manner.